The present invention relates to a system for evenly winding a hose on a reel, and more particularly to a system which employs the hose as a belt for the transmission of the evening motion.
FIG. 1 schematically illustrates a hose and reel system 10 comprising a hose 12 wound on a reel 14. The reel 14 defines a coordinate system of linear coordinates x;y;z and a rotation ρ around the x-axis, and is adapted for a rotation in the ρ direction, around the x-axis, for winding the hose 12 on the reel 14.
Additionally, the reel 14 defines first and second sides 16 and 18, respectively. In order for the hose 12 to wind evenly on the reel 14 and not pile up at one side or the other, when winding, the hose 12 is made to move in an oscillatory motion, in the ±x directions between sides 16 and 18, as shown by an arrow 15.
Various mechanisms are known for producing the oscillatory motion of hose 12, for even winding, as described by the arrow 15.
For example, FIGS. 2A and 2B schematically illustrate a rotating shaft system 20, for providing the oscillatory motion of the hose 12.
As seen in FIG. 2A, the rotating shaft system 20 has a shaft 22, having a length axis along the x-axis. The shaft 22 is threaded by two threads of substantially identical dimensions, but opposite directions: a first thread 24, being a right-hand external thread, is wound in the direction ρ, and a second thread 26, being a left-hand external thread, is wound in the opposite direction −ρ, on the shaft 22. At ends 25 and 27, the first thread 24 and the second thread 26 communicate, so that an element moving on the thread 24 in the −x direction, towards the first end 25, will reverse its direction, upon reaching the first end 25 and begin to move the +x direction, on the second thread 26. Similarly, upon reaching the second end 27, the element will again reverse its direction and begin to move in the −x direction, on the first thread 24.
A motion transmission mechanism 28, for example, a gear 28, causes the shaft 22 to rotate in a single direction around the x-axis, for example, in the direction ρ. A hose carrier 30 is mounted on the shaft 22 and is adapted to move along it, in the ±x directions, on the threads 24 and 26, as shown by the arrow 15. The hose carrier 30 includes a slide 32 which stabilizes it and ensures that the carrier 30 moves only in the ±x directions of the arrow 15. Additionally, the hose carrier 30 includes a hose seat 34 wherein the hose 12 (FIG. 1) is inserted. When inserted the hose 12 moves with the hose carrier 30 in the ±x directions of the arrow 15.
As seen in FIG. 2B, an element 36, enclosed within a cylindrical housing 44 and a cap 42, is adapted to engage with the groves of the first and second external threads 24 and 26, as the shaft 22 rotates. The element 36 has an arched segment 38, serving as an internal thread, which may engage either with the first external thread 24 or with the second external thread 26. As the shaft 22 rotates in the direction ρ, the element 36 moves along either the first or the second external threads 24 and 26, transferring between them at the first end 25 and the second end 27, thus moving in an oscillatory motion, first in the −x direction, along the first thread 24, then in the +x direction, along the second thread 26, and so on, repeatedly, causing the hose 12 to wind evenly on the reel 14.
FIG. 2C schematically illustrates a reel system 40, for evenly winding the hose 12 (FIG. 1) on the reel 14, as known. The reel system 40 includes the rotating shaft system 20 operative for winding the hose 12 on the reel 14 evenly. In accordance with the present example, a gear system 46 transfers motion from the reel 14, to the shaft 22, causing shaft 22 to rotate. It will be appreciated that a belt system or any other motion transfer system, as known, may similarly be used. The motion of the reel 14 may be provided by a motor, by hand, or by any other means, as known.
FIGS. 3A and 3B describe a device 200 for winding and unwinding a cord-like material 230, in accordance with German Patent Publication DE 103 00 960 of Jul. 22, 2004. The device 200 includes a drum 210, which may be rotated by a handle 214.
A shaft 222, mounted on a structure 250, and a pulley 220, configured to rotate around the shaft 222, and having a grove 224, are employed for evenly winding the cord-like material 230 on the drum 210. The shaft 222 includes an cross thread 223, formed as a counterclockwise thread 223L with a first gradient angle and a clockwise thread 223R with a second gradient angle.
By placing the cord-like material 230 in the groove 224 of the pulley 220, and turning the handle 214, the cord-like material 230 causes the pulley 220 to move in the ±x directions, which in turn causes the cable 230 to wind evenly on the drum 210.
A pressure plate 240, pressed against the pulley 220, ensures that the cord-like material 230 does slip out of the guide groove 224.
However, a disadvantage of the device 200 is that the pressure plate 240 increases the frictional forces between the pulley 220 and the shaft 222, thus impeding the motion of the pulley 220 along the shaft 222, in the ix directions.
A motion transfer system devoid of this limitation is desired.